Showground and Castle Hill Station sitesConstruction on the $8.3 billion North West Rail Link at the Showground and Castle Hill Station sites. Pictures: Gene Ramirez and Geoff Jones

Work is progressing rapidly at the Showground Station construction area on the North West Rail Link — Australia’s biggest public transport project.

Castle Hill MP Dominic Perrottet says work is progressing rapidly at the Showground Station construction area.

‘‘More than 34,500 tonnes of crushed rock has already been excavated from the Showground Station area,’’ Mr Perrottet said.

‘‘The Showground site will become a major support site for tunnelling once the tunnel boring machines (TBMs) arrive from Norwest.

‘‘[They’ll] be overhauled at Showground before they start their five-kilometre tunnelling drive towards Cherrybrook.’’ Mr Perrottet said the former The Hills Council building was now being used as a project office while the former depot buildings were used as a machinery workshop.

He said excavation and rock breaking was continuing to create the station area, which will measure 196 metres by 22 metres by 26 metres.

Concrete spraying known as shotcreting is being used to stabilise the walls of the excavated station area.

The entrance to Showground Station will be on the corner of Carrington Road and Doran Drive, next to Castle Hill Showground.

The station — a major commuter hub — will be about 25 metres underground.

‘‘At Showground Station, there’ll be a train at least every five minutes in the peak, which means you won’t need a timetable — customers will just turn up and go,’’ Mr Perrottet said.

He said Doran Drive would be upgraded and widened to two lanes and a new street built between Doran Drive and Showground Road.

Recent work at the Showground includes:

■ Construction of noise barriers around the site to reduce impact on local residents;

■ Realigning noise walls to preserve seven trees on Carrington Road;

■ Installing utilities on-site including electricity, telecommunications, drainage, water supply and a water treatment plant;